Seniority and Incumbency in Legislatures

type="main" xml:id="ecpo12024-abs-0001"> In this article, we elaborate on a strategic view of institutional features. Our focus is on seniority, though we note that this general approach may also be deployed to understand other aspects of institutional arrangements. We have taken the initial game-theoretic model of seniority of McKelvey and Riezman ([McKelvey, R., 1992]), simplified it in order to characterize its fundamental implications, generalized these results in several ways, and extended the model by deriving additional implications. The broad messages of our article, articulated by McKelvey and Riezman as well, are two. First, the endogenous choice of institutional features like seniority by self-governing groups is strategic. While the fine-grained ways of doing things in an institutional context surely serve internal functional objectives, these are not the only objectives. Agents making choices on how to govern themselves have private motivations – in the case of elected politicians they often revolve around re-election. This leads to our second broad message. The institutions through which self-governing groups conduct their business do not exist in a vacuum. They are embedded in a broader context. Those offering functional explanations for various institutional features overlook this. Particular institutional arrangements have effects outside the governance institution itself. These effects, in principle, could be accidental by-products. Our strategic approach, however, argues that they may well be the primary reasons for a practice being instituted.